What Is an API?

Short for application programming interface, an API is a system of protocols that determines how different software should interact with each other. Generally, APIs facilitate an application to request data from another or instruct one application to trigger an action based on data from another application.

APIs are key to achieving this communication, as they can be deployed despite clear discrepancies that may exist in those systems. 

In fact, API traffic was recently estimated by SaltLabs to account for 80% of all internet traffic, while the API endpoints at an organization on average increased almost threefold, from 28 to 89, by 2021, so adoption has been on the increase.

What Is an API Call?

In simple terms, an API call is a request sent to an API to provide information or perform an action.

The client application submits an API call to gather and return certain data from an external server or program. The API does this and sends it back to the client application.

What Do APIs Do?

APIs enable communication between software applications by setting rules for interacting and handling the data transfer. APIs are the reason why users can access information from one digital application on another, despite the two using completely different software and programming from each other. 

In addition to determining how software systems should communicate, APIs allow applications to exchange data between them and share the retrieved information with end-users.

Ultimately, an API is a go-between between one or more software systems and, as such, it allows the communication, accessibility, and interoperability that is needed to complete various tasks.

Because there is an ever-present need for multiple software applications to communicate with each other, there are countless examples of APIs and the functionality they enable.

How Do APIs Work?

APIs work automatically at a software application’s backend (its code) whenever an end-user makes a command at the frontend (its user interface). They function as a middleman, translating one application’s requests and data for use in another, after a client application has submitted such a request (an API call).

Here’s an example of a simple workflow:

  1. You want to sign up for a new account at an eshop, and the eshop has the option to sign up via Google.
  2. You select the Google account option. At this point, the client application sends an API call to Google’s server.
  3. Google’s server gathers key information from your profile e.g. your email address and full name, and submits it to the API.
  4. The API forwards this information back to the eshop.
  5. Thus, your details are pre-populated in the new account form with information from Google, and account creation is sped up.

Another common example we can look at comes in the form of weather apps. When you open a weather app, you see the current temperature and other details. This is achieved by an API retrieving pure data from the database of the weather service, then relaying it to the user graphically on the application. In this case, the request is sent as soon as you tap to open the app.

This ability of an API to access the info stored in outside databases is not always utilized graphically. APIs are also an important part of analysis software that serves many different verticals, including online fraud detection. Many of these programs use APIs to access data entirely on the backend which, for the most part, does not reach the end-user.

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Types of APIs

APIs currently available can be generally categorized by architecture, or by ownership and security:

Open APIsOpen-source APIs available to all developers.
Partner APIsCreated by a partner business, these can be a result of SaaS services. Access needs to be granted by the partner.
Internal APIsDeveloped for internal use by a specific company.
Composite APIsAPIs that query information from different endpoints, so that the client information receives consolidated data.
Web APIsA framework for APIs that are part of the world wide web and can be accessed on web pages via HTTP.
REST APIs (or RESTful APIs) This type of architecture is employed in most web APIs and follows a series of guidelines that allow for quicker and more secure transfer of information by being cacheable, stateless, layered, etc.
SOAP APIsThese APIs employ an XML document to exchange information. They are strict and rule-based.
RPC APIsRPC protocol APIs trigger processes, executing scripts instead of transferring data.
GraphQL APIsThis open-source query language for APIs is focused on providing the client application with the exact data it requests and nothing more.

3 Examples of API Functionality

The potential applications of APIs in programming are literally limitless, akin to counting the number of possible conversations two humans could have, and what their takeaways might be.

Of course, some of these applications are more common than others, with proven effectiveness. Here are a few API-based online interactions which most people have probably dealt with at some point.

1: Onboarding at a New Service

Whenever you sign up to a new online service such as a social media website by entering your personal details into a form, the website that you used will send you an email asking you to verify your email address.

This is a process of authentication that is often facilitated by APIs: APIs factcheck your details by querying different databases, then ensuring your info is then sent safely to the website’s servers, all before you are asked to verify your email address.

2: Making an Online Payment

APIs use security measures, such as encryption, to help ensure that online payments are carried out securely and efficiently. If you have ever filled out a payment form online that then led to a verification page from your card’s bank, it was an API that makes this transfer and authentication process possible.

Application programming interfaces enable communication between the payment processor form (e.g. a PayPal form that users have to enter their debit card details into) and the cardholder’s bank.

Without an API, the process would be far less safe and efficient. However, like all software, APIs can be hacked, which is why developers should utilize tools such as encryption.

3: Carrying Out a File Conversion

It is easy to carry out a file conversion using a device: A common example is changing a word processor document to a PDF. An API allows an application to pass a file to another computer program and request that that program carries out the file conversion.

The conversion could not take place without the API’s communication between the original software (e.g. Microsoft Word) and the program whose file format is required by the end-user (e.g. Adobe PDF), facilitating the translation of the document. During the conversion process, another API might handle any permissions the software requires. If a document is being stored in the cloud, it may require approval to be moved out of it.

Why Choose to Use API Calls?

Many businesses rely on API calls – another term for a request made to an API – to power their data-driven software because they are efficient, convenient and resourceful. APIs offer automation and security, and allow any software to use data from other databases, rather than each company having to build its own for every required dataset. Your smartphone’s weather app would rather make a call to an existing current weather database than construct its own.

In terms of convenience, API calls provide businesses with a seamless process to direct users to required software outside the business or website. This way, third-party solutions can handle things like payment processor forms or multi-factor authentication, without having to open a new window or app. 

APIs also ensure that each organization can select the functionality that satisfies its needs from various vendors, deploy it quickly and also integrate it into its workflows and platforms.

For example, SEON provides several modular API solutions for fraud prevention, including Email API, Email Verification API, Phone API, AML API, etc so that customers can choose and use just the ones that suit their needs. Several APIs can also be combined into one, as can be seen with SEON’s Fraud API, which combines the Email, Phone and AML APIs.

Such convenience also allows organizations to more easily connect and share data that helps to inform their business operations. In fact, the API calls themselves can be tracked and, if they reach a suspicious number from a single IP address, the resultant data could be used to help fight fraud.

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APIs and Fraud

APIs relate to fraud in three main ways:

  1. By providing a point of access to systems and workflows, APIs can be subject to cybersecurity attacks such as API exploits.
  2. APIs can provide modular, customizable tools for organizations to fight against fraud and scams.
  3. APIs allow organizations to combine different fraud prevention solutions into one stack, for increased efficiency.

In fact, a rise in API attacks was seen as an emerging fraud trend for 2022 by Frank on Fraud, though the follow-up article at the end of the year did not identify as bad a situation as was initially anticipated.

In the fight against fraud, on the other hand, APIs allow companies to make use of multiple software at the same time, better integrate them into workflows, and pick and choose the features that they want to deploy.

Overall, API availability in the form of fraud prevention allows it to be more flexible, customizable, and compatible with existing infrastructure.

How Can APIs Fight Fraud?

APIs can fight fraud by compiling data about incoming traffic to assess it for signs of malicious intent and transmitting this information to a central platform as part of a risk stack.

Some of this data might be graphically presented for fraud teams to perform manual checks. Fraud investigation software takes data returned by API lookups and assigns different data points a risk-based score, to inform an overall score that tells the organization how likely an individual is to be a fraudster. These APIs also allow companies to customize their software to suit their individual appetite for fraud and risk.

For example, if an eshop has found that it has had several attempts at checkout using a series of stolen cards, it could adjust data from API lookups to be stringent against users that demonstrate similar behavior. Potentially fraudulent traffic could then be taken an extra verification page. This effectively closes the gate on many fraudsters.

Leveraging a fraud prevention program that utilizes APIs to secure online payments, user accounts and other systems helps grow a reputation for being a safe place to do business. Maintaining such a reputation, once earned, will help to keep legitimate customers returning while deterring malicious ones.

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